AgentsxAINovember 19, 2025

xAI releases Grok 4.1 Fast and an Agent Tools API for tool-calling agents

Official announcement Benchmarks & resources

A snowy owl with spread wings flying through streams of red data. — Official imageImage: xAI (opens in a new tab)

Grok 4.1 Fast at a glance

xAI positioned Grok 4.1 Fast as its strongest tool-calling model, with a 2M-token context window and low per-token pricing, alongside server-side agent tools.

What changed with Grok 4.1 Fast

On November 19, 2025, xAI released Grok 4.1 Fast in reasoning and non-reasoning variants and launched an Agent Tools API. The tools give agents server-side access to web search, X search, code execution, file and collection search, and remote MCP servers.

xAI says the model is tuned for fast, accurate agent work such as customer support and finance, and reports a 100% score on the τ²-bench Telecom test (verified by Artificial Analysis) plus 72% on Berkeley Function Calling v4. These are vendor-reported results.

Grok 4.1 Fast benchmarks and pricing

Values are copied from the linked source on the date shown. They are not IA Compa measurements.

Input price per 1M tokensas of Nov 5, 2026 · Source for Input price per 1M tokens: x.ai (opens in a new tab): $0.20
Output price per 1M tokensas of Nov 5, 2026 · Source for Output price per 1M tokens: x.ai (opens in a new tab): $0.50
Context windowas of Nov 5, 2026 · Source for Context window: x.ai (opens in a new tab): 2M tokens

Where to compare Grok 4.1 Fast

Independent leaderboards and official resources for comparing this model yourself. Rankings change often; each site shows its own current data.

Leaderboards

General leaderboards

Official resources

Why Grok 4.1 Fast matters for businesses

For agencies, the draw is cost: the listed price is $0.20 per 1M input tokens and $0.50 per 1M output tokens, with tool calls from $5 per 1,000 successful invocations. That makes high-volume support or lookup agents cheaper to run, though results should be tested on your own workflows.

Put it to work: AI Agents

Sources for this story

Grok 4.1 Fast and Agent Tools API (opens in a new tab)
xAI · x.ai
Official
Release notes (opens in a new tab)
xAI Docs · docs.x.ai
Official

Last verified: November 5, 2026. IA Compa summarizes public announcements for business readers. We are not affiliated with the companies mentioned. Always confirm details, pricing, and availability with the official source.

#llm
#xai
#grok
#agents
#tool-calling

Aug 12, 2026xAIModels
xAI ships Grok 4.6 with a 500k context window for long-running agents
Grok 4.6 builds on Grok 4.5 with more self-testing on long tasks and stronger visual and interactive output, at the same base API price.
Image: xAI
Aug 11, 2026xAIAgents
xAI introduces Grok Bot, always-on AI teammates on cloud computers
Grok Bot, launched in beta, lets subscribers create persistent agents that work in a shared cloud computer, keep memory, learn routines, and ask for approval before key steps.
Image: xAI
Nov 4, 2026xAIAgents
Grok Bot can now place phone calls for you, with a live transcript and a take-over button
On November 4, 2026, the official Grok Bot account said the agent can now make phone calls. The user confirms each call, follows a live transcript, can take over or end it, and gets the result in chat. Teslarati reports calls are limited to US businesses for now.